If I understand what you have done (and I am not sure that I do!), it isn't a fair comparison at all.

What matters is that you compare images from the same size print. This has been discussed in multiple DPreview forums.

You must either enlarge the m4/3 image or reduce the size of the a7r image to do this or you are looking at per-pixel sharpness. Per-pixel sharpness favours cameras with lower pixel count.

The Nikon 800E users went through this incorrect way of comparing images in great detail. If I remember correctly there was someone who refused to accept that you can't simply compare per pixel sharpness.